Wednesday, 16 February 2011

Irish Times BANG - Cold Fusion

A mere 93 million miles away from Earth is the Sun, our closest star. The Sun is so massive that it contains 98% of the total matter of our solar system and that 1.3 million Earths would fit inside it. The Sun is essentially a massive ball of hydrogen and helium, burning brightly for the last 4.6 billion years and supplying our planet with all its energy needs, either directly or indirectly. But what powers this massive fire ball. The answer is NUCLEAR FUSION.

Deep within the Sun’s core, where the temperature reaches over 15,000,000 oC and the pressure exceeds 340 billion times the pressure on the Earth’s surface, atoms of hydrogen collide with each other at extreme speed forming helium and releasing the excess energy.

Every second, in our Sun, 700 million tonnes of hydrogen are converted into helium, releasing 384 Yottawatts of energy (that’s an astonishing 384,000,000,000,000,000,000,000,000W every second)!

So wouldn’t it be useful if we could utilise the fusion reaction of hydrogen for the production of energy on Earth? Absolutely, but the problem is that re-creating the high temperature and pressure of the Sun on Earth isn’t easy. Hydrogen nuclei strongly repel each other normally but in the high temperatures and pressures of stars they collide furiously releasing energy.

Fusion power has been achieved on Earth though, primarily in nuclear fusion bombs (Hydrogen Bombs), but also in controlled experiments but commercial fusion power for the production of electricity maybe several decades or so away. Several methods are being explored in order to do this including the use of lasers to superheat the hydrogen.

However, there could be another option, one that may be able to avoid the need for such high temperature to initiative fusion reactions – we’re talking COLD FUSION.

Cold fusion is a proposed mechanism for the production of energy which would see hydrogen atoms colliding at around room temperature.

The idea originated from experiments carried out by Stanley Pons and Martin Fleishmann, two well regarded electrochemists, in the late 1980’s. During their experiments with electrolysis they noticed an unexplained increase in temperature (from 30oC to 50oC), which they attributed to the fusion of hydrogen atoms in the “heavy water” they were using. Heavy water contains deuterium – atoms of hydrogen with a neutron in their nucleus.

However, problems with their theory soon arose after the scientists were unable to repeat their experimental results and it was discovered that some of their results had been falsified.

Nevertheless, since Pons and Fleishmann’s failed experiments, many scientists have tried in earnest to generate cold fusion reactions in the lab, but with little success.

Recently two Italian scientists, Andrea Rossi and Sergio Focardi of the University of Bologna, announced that they developed a cold fusion device capable of producing 12,400W of power with an input of just 400W.

Rossi and Focardi claim that not only do they know how to build a cold fusion reactor, they claim they already have. The say they have tested it, are able to mass produce them and will have them ready to ship in the next three months!

Unfortunately, however, the two admit that they don’t really understand how their reactor actually works but maintain it takes in nickel and hydrogen and produces copper and a lot of energy. They also claim their reactor has been powering their factory for the last two years but won’t tell anyone where it is.

The scientific community want little to do with Rossi & Focardi and the pair had to create their own journal in order to get their scientific paper published. This isn’t a good sign that cold fusion has actually been discovered!

Cold fusion, or indeed fusion power in general, would be extremely useful. Huge amounts of energy could be produced with little energy input, potentially removing our dependence on fossil fuels.

So, cold fusion is likely to remain the alchemy of modern science for a while yet and isn’t likely to contribute to the national grid any time soon either (unless our Italian friends are telling the truth).

It seems more likely that reliable “hot” fusion will form part of our planet’s energy production in the coming decades but, for the moment at least, your best chance of seeing fusion power in action is by studying the Sun!

40 thousand years. If you calculate the mean free path of a photon inside the sun. It spends that long bouncing off things from when the photon is created until it gets out of the sun. then less then ten minutes later it hits us. http://www.astronomycafe.net/qadir/ask/a11354.html